[AMPS] Carbon Composition Resistors (Swamping Network for Halllicrafters HT-33 A amplifier)

[km1h@juno.com]

On Thu, 27 Aug 1998 19:21:46 -0500 "Jim Zellmer" <zellmer@raccoon.com>
writes:
>
>I have a Hallicrafters HT-33A amp sitting on my project shelf.  The 
>orginal
>swamping resistor network consisted of 3 200 ohm 20 watt globar 
>resistors.
>One is missing and the others have changed in value.
>
>I might add that I chased down the original manufacturer of the 
>Glowbar
>carbon resistors.  That particular size would be a special order and 
>was
>going to cost about $50 each with a $250 setup charge.  I suppose the 
>cost
>would go down with a larger ordrer.
>
>
>Would a network of  the MOF resistors described below work, assuming 
>that
>the use of a 100 watt exciter work as a suitable replacement for the
>origninal Glowbars?  I was thinking of using a seriers parallel 
>network of 6
>100 ohm resistors.  Where do you order the Matsushita 3w-rated 100 ohm 
>MOF
>resistors described below?
>
>It would be really nice to get the SX-101, HT-32 and HT33A going for 
>the
>cold nights a head
>
>TNX ES 73
>
>Jim Zellmer,  KA0VSL
>

I have an alternate that may work Jim.

The old National NCL-2000 used a swamping network made up from 14 180 Ohm
7W non inductive resistors. 
I have several complete networks as removed from 6M conversions....$15
shipped.

No experience with metal oxide in that application but it would appear to
be feasible and any inductive reactance could be tuned out with a
cap......same principle as used with open frame relays on the higher
bands.

73  Carl  KM1H 

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